High temperature intergranular damage and fracture

The estimation of the degree of intergranular damage based on the quantitative metallography of cavitation should be the starting point of any remanent life assessment route. Unfortunately, only limited quantitative measurements are available to provide information on the extent of cavitation in the fracture state in various materials and under different high temperature loading conditions. Therefore, the present work attempts to highlight the problem areas just in this respect. A critical amount of intergranular damage accumulation is defined and its applicability as a fracture criterion is demonstrated by recent experimental results. Finally, the application of the percolation model of cavitation to explain theoretically the critical amount of cavitation is discussed.